Touch panel, as a new input device, is easy to use compared with conventional input means such as keyboard and mouse. With the development of touch technology, in-cell capacitive touch panel technology is most widely used nowadays. This is because the in-cell capacitive touch panel can be lighter, thinner, and has fewer processes compared to other touch panels, which can reduce cost while realizing integration of touch-control and display.
FIG. 1 is a structural diagram of an in-cell capacitive touch panel in the prior art. As shown in FIG. 1, the touch panel comprises a backlight 15, a lower glass substrate 16 formed on the backlight 15, thin film transistors 24 formed on the power glass substrate 16, pixel electrodes 19 and common electrodes 17 formed on the thin film transistors 24, an upper glass substrate 20 opposite to the lower glass substrate 16, color filter layer 22 and a black matrix 23 formed on a side (i.e., inner side) of the upper glass substrate 20 facing the lower glass substrate 16, transparent electrodes 21 formed on an outer side of the upper glass substrate 20, and liquid crystal 18 filled between the upper glass substrate 20 and the lower glass substrate 16. The common electrode 17 and the transparent electrode 21 form a touch capacitor, in which the common electrode 17 functions as a first pole of the touch capacitor and the transparent electrode 21 functions as a second pole of the touch capacitor. A touch-control electric field is formed between the first and second poles of the touch capacitor. When the display screen is touched by a finger, the touch-control electric field may be changed, and thus induced current is generated on the second pole of the touch capacitor. The location at which the touch occurs is positioned by an external touch sensing chip based on the induced current, and positioning signal is fed back to a host so that the location at which the touch occurs may be determined, contents needed to be displayed may be controlled correctly based on the location at which the touch occurs, and thereby integration of touch-control and display may be realized.
However, in the prior art, there are problems as follows. In the touch panel, in addition to the touch-control electric field between the transparent electrode and the common electrode, there is a display electric field for controlling liquid crystal display between the pixel electrode and the common electrode; since these electrodes in the touch panel of the prior art are arranged in the respective positions as shown in FIG. 1, the touch-control electric field and the display electric field may partially overlap. When a touch occurs, the touch-control electric field and the display electric field may interfere and interact with each other, which will reduce not only display quality but also accuracy of determination of location where touch occurs.